Does the Presence of Precipitation Affect Behaviour in a Horse, in Particular the Behaviour of ‘Rest’?

Updated on September 30, 2014

Abstract

The purpose of the experiment was to observe behaviour. The particular behaviour of study was: Does the presence of precipitation affect behaviour in a horse, in particular the behaviour of ‘rest’?

The hypothesizes were: H0 – The frequency of the animal behaviour ‘rest’ is not affected when precipitation is present in the environment, H1 – The frequency of the animal behaviour ‘rest’ is affected when precipitation is present in the environment.

The wider results could supplement the human understanding of the requirements of horses (for example, is it better for the welfare of a domesticated horse to live in a stable, without precipitation, or a field, where precipitation is always a threat?) but can also have a wider impact of knowledge (for example, did the Alaskan Pleistocene horses become extinct because of problems with thermoregulation when high levels of precipitation were present?).

The results were found by observing the behaviour of three Percheron/Paint crossed horses who reside in a fenced field next to the University of Glamorgan in Treforest, while using a rain gauge to measure precipitation.

It was found that the behaviour ‘rest’ has no statistically significant variance with levels of precipitation.

Further topics of research could include looking at the difference between the core body temperature of the horse being observed could be recorded and see the correlation between it and the frequency and the intensity of the ‘rest’ behaviour.

Introduction

The purpose of the experiment was to observe if the presence of precipitation affected behaviour in a horse, in particular the behaviour of ‘rest’.

The current understanding about rest behaviour is that, as Cymbaluk and Manitoba (2001), stated “horses stop foraging and stop moving to conserve energy” when it is raining and cold. However, this information is from the viewpoint of an animal welfare prospective, e.g. how best to care for horses in extreme conditions. Thus, no specific scientific observations or experimentations had been completed to prove this theory and they had to be completed to back up the ideas.

Regardless, Weinstock et al. (2005) agreed with this theory. They described horses as being highly adaptive, since they are capable of “morphological variation in terms of adaptation to different environments”. Yet it could be said that Weinstock et al.’s results are limited, since it was not directed at precipitation specifically but more focused towards low temperatures. Thus, further observations were necessary to reach the required specificity.

Methodology

Our primary original observations were conducted within the context of Percheron/Paint crossed horses who reside in a fenced field next to the University of Glamorgan in Treforest. The horses were observed for one hour when there was no precipitation to understand their natural behaviours, to enable an ethogram to be created. A preliminary draft of an ethogram was produced [Table 1], based on the findings.

A secondary phase of observation was then completed. A horse was observed for one hour every day between 16:00-17:00 from 08/02/13 until 11/02/13 and the amount of precipitation during this time was also recorded using a rain gauge.

The experiment was then part repeated for one hour on two additional horses to ensure the results were consistent.

To control potential confounding variables, it was ensured that behaviour was not altered because of the need for food, so the times 16:00-17:00 were carefully selected because the horses get fed at 7:30 and 20:00. Also, the owners of the horse assured the researches that the horses are on no medication and the food they received was the same on all observation days. The temperature was also recorded with a thermometer every five minutes and the mean for the hour found to make sure that it was the presence of the precipitation that was causing any effects and not the effect of the temperature. However no attempt was made to control the temperature or other confounding variables because the horse must be observed in its natural environment and otherwise artificial components of the environment may alter the horse’s behaviour.

The data was collected using the ethogram and the following were recorded: the frequency (the number of resting behaviours in one hour), the latency (average time between each behaviour), the intensity (whether the horse lay down or not) and the duration (how long the behaviour lasted for, categorised into: 1-4 seconds-short rest; 5-10 seconds-medium rest; 11+ seconds-long rest for more simple data collection).

The data was then statistically analysed using a linear correlation analysis because this statistical test determines whether there is a relationship between the two sets of variables. This was calculated using the programmes Excel and SPSS. Originally, the frequency of resting behaviour was going to be statistically analysed, however it became apparent that the duration of the ‘rest’ behaviour would be a more accurate measurement.

Results

The key results are that the behaviour rest has no statistically significant variance with levels of precipitation.

A linear correlation analysis was chosen (and so the equation r=(cov(X, Y))/ơxơy)) to determine whether there was a relationship between the two sets of variables. This test was chosen because the values came from a paired study (so the correlation is not between two univariate distributions), the two variables were both observations or outcomes and both x and y are normally distributed. The results used were those collected from Table 2.

Table 2 The Frequency, Intensity, Duration and Latency of the Behaviour 'Rest' of a Horse in One Hour

The slope of the trend line on Figure 1 suggests that the two variables had a positive correlation however after doing a linear correlation test to investigate whether the ‘Mean Precipitation Level/ mm’ is a factor in ‘Total Time Rested for/ minutes’, the correlation coefficient 0.783185 was calculated. Since 0.783185<0.9000, it was found that the mean precipitation level and the total time exhibiting ‘rest’ behaviour was not significant to a 0.05, 0.025, 0.01 or 0.005 level. It would be interesting to see this experiment replicated, however, to see if a greater sample size would alter the results found.

Figure 1 The Mean Precipitation Level Hour/mm and the Total Time Exhibiting 'Rest' Behaviour, in one hour

Similar results were also found when other data was used in this manner.

The correlation coefficient between ‘Mean Temperature/oc’ and ‘Total Time Rested for/ minutes’ was not significant because 0.536512<0.9000.

The correlation coefficient between ‘Mean Precipitation Level/mm’ and ‘Short Frequency of Resting in One Hour’ was also not significant, since -0.61216<0.9000.

The correlation coefficient between ‘Mean Precipitation Level/mm’ and ‘Medium Frequency of Resting in One Hour’ was not statistically significant because -0.5447<0.9000.

The correlation coefficient between ‘Mean Precipitation Level/mm’ and ‘Long Frequency of Resting in One Hour’ was not significant since0.72449<0.9000.

The correlation coefficient between ‘Mean Precipitation Level/mm’ and ‘Average Latency of Resting Behaviour/minutes’ was not significant because -0.61216<0.9000.

Thus, since the experiment did not show statistical significance between the presence of precipitation and the behaviour ‘rest’ in a horse, the alternative hypothesis should be rejected and the null hypothesis accepted.

Discussion

The purpose of the experiment was to observe if the presence of precipitation affected behaviour in a horse, in particular the behaviour of ‘rest’.

This area of research could greatly improve the human understanding of the requirements of horses. For example, is it better for the welfare of a domesticated horse to live in a stable, without precipitation, or a field, where precipitation is always a threat? There is also the potential to have a wider impact on knowledge, such as, did the Alaskan Pleistocene horses become extinct because of problems with thermoregulation when high levels of precipitation were present?

The results showed that the presence of precipitation did not significantly affect the ‘rest’ behaviour in a horse.

This result does not fit with most current theories. However, this is perhaps an indication that the horse would need to be observed for a greater number of days to increase the sample size for the critical values tables. If this was done, the validity of the data would then be improved.

Such research includes, Cymbaluk and Manitoba (2001), who stated “horses stop foraging and stop moving to conserve energy” when it is raining and cold. Weinstock et al. (2005) agreed, describing horses as being highly adaptive, since they are capable of “morphological variation in terms of adaptation to different environments”.

This could be because, when the horses were too cool because their temperature could have been lowered by the surrounding precipitation, they needed to stand still to conserve energy, and so entered this ‘rest’ behaviour (McDonnell and Poulin, 2002). However, when there were low amounts of precipitation this did not happen a significant amount because the horses were able to regulate their own body temperature, to an extent. Brown et al. (2003), believed this self-regulation of temperature when it was stated “in cold weather the hairs [of horses] stand on end, so increasing the amount of air trapped in the coat which also grows longer, thus providing yet more protection [when] in hot weather the hair lies flat and is much shorter”. The hairs are able to lift in this way because the arrector pilli muscles beneath the skin relax, which causes arteriole muscles to relax, causing vasodilation (Serwey and Jewett, 2012). Therefore, the horses are able to keep themselves warm because the warmth of the blood is closer to the skin, so thermal conduction can occur.

Csurhes et al. (2009), on the other hand, had different ideas. They said that “widespread rainfall improves recruitment and avoids heavy losses caused by drought”. This means that the presence of precipitation is vital for the survival of horses and so they have adapted to become used to it in their environment. This theory provides an explanation as to why the precipitation did not affect the behaviour of the horse, because it is already adapted to this common environmental occurrence.

If this experiment was to be repeated, it would be interesting if the core body temperature of the horse being observed could be recorded and see the correlation between it and the frequency and the intensity of the ‘rest’ behaviour. If this was done, it would give clarity to the experiment because the extent to which the precipitation levels are affecting the body temperature of the horse is currently fairly unclear.

In conclusion, the experiment would need greater validity, through the use of a greater sample size and observation time. Currently it has been found that the presence of precipitation does not significantly affect the ‘rest’ behaviour in a horse, possibly because horses have acclimatised themselves, through evolution over the years, to the environment of the UK. Further study could include looking at the population validity of the data, by seeing how well horses from outside the UK are adapted to their environments also.

More by this Author

Genetic variation today is limited because of humans and the human selection of desirable traits. This repeated process causes populations to form a genetic bottleneck. In the 20th century, the importance of induced...

Modern breeds of dogs are only approximately 200 years old and so have spent most of their time as wolf-dog hybrids [Figure 2]. It is uncertain exactly when dogs were first domesticated, but it appears to be...

Introduction
My aims and objectives of this project were to develop my understanding and knowledge on a topic which fascinates me-that of cancer research. Not only is it a topic which causes great distress to the...